Lately, the electronic devices having the contact detection unit such as a touch sensor have been increasingly used for mobile terminals such as mobile phones. As a method to detect a contact by an operator, there are known variety of types, such as a resistive film type, a capacitive type, an optical type and the like. Those types detect the contact by a contact object such as an operator's finger, a stylus pen and the like. As the electronic device having the contact detection unit, a touch panel having the contact detection unit and a display unit laminated to each other has been known. In the touch panel, the display unit is disposed on a rear face of the contact detection unit and displays graphical images of characters and buttons (objects) of buttons and the like. When the operator presses the object displayed on the display unit, the contact detection unit detects a contact at a pushed position. A technique to provide a tactile sensation to the operator in response to pressing with a predetermined pressure load or higher has also been known.
Incidentally, there are electronic devices that execute predetermined operations based on the pressure loads. Japanese Patent Laid-Open JP11-119882A, for example, discloses a key input apparatus enabling selection of a plurality of characters assigned to one key based on the pressure load.
According to the technique disclosed in JP11-119882A, however, when the operator, for example, presses down a key assigned Japanese characters in an “A” row by mistake despite an intention to operate a key assigned Japanese characters in a “KA” row, the operator needs to remove the finger from the key assigned the “A” row and press another key such as a “cancel key” to correct an input character. Therefore, the number of times to touch the key is increased and thus operability is deteriorated. Accordingly, it has been desired to improve the operability in an erroneous operation when a predetermined operation is executed based on the pressure load.